Carbon bisulfide retort



June 12, 1956 l. c. MACDOUGALL 2,750,264

CARBON BISULFIDE REToRT /g IN VEN TOR. //4 Iver C. Maca/caga# June 12,1956 c. MACDOUGALL 2,750,264

CARBON BISULFIDE RETORT 5 Sheets-Sheeil 2 Filed Aug. 21, 1952 Ido Mm au.f w. vl.

ORA/SYS A MEMBER oF 'rf/E F/ June 12, 1955 l. c. MACDOUGALL CARBONBISULFIDE RETORT 3 Sheets-Sheet 3 Filed Aug. 2l, 1952 IN V EN TOR. [ver6. Macdougcz/l M L e 5M n E wm m F nl o H a K n .u m M A Y B FLL UnitedStates Patent O CARBON BISULFIDE REToRT Iver C. Macdougall, Bronxville,N. Y., assignor to Stautfer Chemical Company, a corporation ofCalifornia Application August 21, 1952, Serial No. 305,655

11 Claims. (Cl. 23-277) This invention relates to improvements in themanufacture of carbon bisulphide and particularly to an improved retortconstruction.

lCarbon bisulphide is commonly produced by reacting sulfur vapor andwood -charcoal at high temperatures, e. g., around l4501650 F., in aretort. The retort is usually positioned vertically in an externallytired furnace, carbon being fed in at the top and sulfur at the bottom.While the reaction between carbon and sulfur is slightly exothermic,once the two reactants are at reaction temperature, considerable heatinput is required to raise the sulfur and the carbon to reactiontemperature. It has been deemed impractical heretofore to make theretort of large diameter because of the high furnace temperaturerequired to-force the necessary heat to the center of the carbon-mass inthe retort.

The retorts are generally made of cast iron and are relativelyshort-lived on account of the deteriorating effects of the hightemperatures externally applied, the i corrosive effects of sulfur andthe carbon bisulphide. Also,- because the carbon utilized is usuallywood charcoal, ash constituents are present; it is therefore necessaryto clean out the retorts periodically. This is done by opening theretort to the atmosphere, the sulfur and carbon bisulphide present inthe retort being released to the atmosphere; the retort is then pokedwith a bar so that any adhering ash on the side of the retort is removedmechanically. The admission of the relatively cold air to the retortresults in considerable thermal shock to the retort. In addition, thesurface of the cast iron is usually covered with a layer of ironsulphide. The thermal shock resulting from admission of the atmosphericair during cleaning usually results in this sulphide layer cracking sothat its protection is lost and additional iron is subsequently used upin forming additional sulphide, when the retort is again placed inoperation.

Because of the relatively small size of the retorts, it is necessarythat a relatively large number be employed to obtain the necessaryproduction of carbon bisulphide in a commercial quantity. Consequently,installation and maintenance costs are high; retort replacements usuallyconstitute a relatively large item in the operating cost.

In accordance with the present invention, I provide a carbon bisulphideretort in which the mass of carbon is heated to reaction temperature bythe sulfur vapor introduced for reaction with the carbon. Thiseliminates any necessity for heat transfer to the carbon through theretort wall so that ash and clinker formation on the side walls of thefurnace are largely obviated. Further, since the sulfur vapor can beheated to a temperature such that it can carry to the carbon the heatnecessary to raise the carbon to reaction temperature, the reactionbetween the sulfur and carbon present in the retort is made more nearlyuniform so that much less carbon passes through the retort and is notreacted with sulfur. This last follows from the fact that whenever thesulfur cornes into contact with the carbon, the two can react inasmuchas the sulfur carries suicient heat to raise the carbon to reactiontempera-f ice* ture. In this connection, it should be pointed out thatonce the carbon and sulfur are at a temperature in the range whereat thereaction between the two can take place, the reaction between them toform carbon bisulphide is slightly exothermic and not endothermic, as isfrequently stated. Concomitantly, the sulfur content of the exit gasesfrom the retort is materially reduced because, whenever sulfur andcarbon come into contact, the former carries the heat necessary to thereaction. In previous retorts, the sulfur may pass over carbon, but ifthe latter has not been heated to reaction temperature, the sulfur willpass through without reacting to provide a problem in the carbonbisulfide condensers.

It is the generally broad object of the present invention to provide anovel, improved carbon bisulphide retort.

A further object of the present invention is to provide a carbonbisulphide retort of such construction as enables the heat from thefurnace to be carried into the carbon body by the sulfur vaporintroduced, the carbon being raised by the heat from the sulfur vaporsto a temperature whereat it reacts with the sulfur.

The invention includes other objects and features of advantage, some ofwhich, together with the foregoing, will appear hereinafter wherein thepresent preferred form of retortconstruction of this invention isdisclosed.

Referring to the drawing,

Figure l is a side elevation, partly in section, of one form of carbonbisulphide retort embodying the present invention.

Figure 2 is a plan View of the retortshown in Figure l.

Figures 3, 4, 5 and 6 are respectively sections taken along the lines3-*3, 4 4, 5-5 and 6-6 in Figure l.

Figure 7 is a view along the line 7--7 in Figure 8 and showing amodified form of reactor together with a sulfur Vaporizer.

Figure 8 is a side view, partly in section, of the sulfur feeder andretort of Figure 7.

Referring to the drawings and particularly to Figures l6,-a suitablefurnace has been indicated generally by numeral 10, the furnace beingsuitably heated by the burning of coal, oil, natural gas or othersuitable fuel. Supported upon a furnace wall is an outer tubular vessel12 having a bottom 13 suitably supported upon the floor of the furnace.The outer vessel 12 includes several spaced vertical feet 14 on theupper face of bottom 13. A sulfur inlet 17 is provided adjacent the oor13 for the feeding of liquid sulfur from a source external to thefurnace.

An intermediate tubular vessel 18 is mounted within the outer vessel 12,the intermediate vessel including a plurality of depending feet 19 whichrest upon the feet 14 on the bottom 13 of the outer vessel 12. The upperend 2l of the intermediate vessel is provided with spaced ribs 22adapted to seat upon either side of an internal rib 23 on theintermediate vessel 12 to support the upper end of the intermediateVessel in a spaced relationship to the outer vessel 12, as appears inFigures l, 4 and 5. The intermediate vessel 18 includes a tloor 26 uponwhich ash collects, a suitable ash outlet 27 being provided, ashwithdrawal chute 28 extending from the outlet 27 through the outer wallof outer vessel 12 and external of the furnace so that ash collectingupon the bottom 26 can be periodically removed; the ash chute 28 issuitably sealed in the outer wall as at 29 and within the outer wall ofthe intermediate vessel as at 30.

An inner tubular shell 31 is mounted within the intermediate shell 18.The shell 31 is flanged as at 32 and is supported upon the flanged end33 of the outer shell. The tubular shell 31 depends to adjacent thebottom 26 of the intermediate shell to carry carbon down to within theintermediate shell.

It is to be noted, as appears in Figures l and 4, that the inner shell31, the intermediate vessel 18 and the outer vessel 12 are substantiallycircular in cross section and are concentrically arranged about a commonlongitudinal axis. While a circular cross section for the shell, theintermediate vessel and the outer vessel is preferred, it should beobvious that one can use other cross sectional shapes as long as thetubular vessels and shell are suitably spaced from one another so thatsulfur passing between the vessel and shell walls is suitablysuperheated. The circular shape shown is preferred, however, because ofthe vessels and shell being easily made in this fashion; one can usevessels and shell which are rectangular or ovoidal in section; what isessential is that shell 31 deliver carbon to within the outer vessel 12and that the sulfur pass between the vessels and circulate uniformlyover the inner wall of the outer vessel and over the outer wall of theshell so that the carbon mass in the shell is heated to a minimum extentYfrom the inner wall of the shell and to a minimum extent by thesuperheated sulfur vapor which rises.

Referring particularly to vFigures l and 2, a tubular receptacle 41 ismounted upon the flange 33 of the outer vessel 12, the receptacle havinga flange 42 secured to ange 33 on the outer vessel by a plurality ofbolts 44. A carbon inlet-46 is provided upon the top of the receptacle,a cover plate 47 being removably positioned over the inlet by a lever 48hinged upon studs 49, the latter being secured on each side of a pillart) rotatably mounted on the receptacle by a stud 51. The arm 48 issecured in covering position by a clevis 52 hinged upon an ear 53 on thereceptacle, the clevis carrying a threaded shaft 54 and a hand wheel 56for fastening the lever and its cover in position over the opening 46.Carbon bisulphide rising from within the inner vessel 31 is taken offthrough an outlet 61 in an upper portion of the receptacle 41.

In operation, with the retort heated Ato reaction temperature by thefurnace and with sulfur fed ,substantially continually on to the door 13of the inner vessel 12, the sulfur vapor passes upwardly between theoutervessel 12 and the intermediate vessel 18. The sulfur vapor becomessuperheated as it moves over the inner surface of the outer vessel 12;the sulfur vapor finally passes over the upper end of the intermediatevessel and then downwardly in the space between the inner wall of theintermediate vessel 18 and the outer wall of the shell 31. Finally, thesuperheated sulfur vapor enters the inner .shell 31 and passes upwardlythrough the carbon mass present. Since the sulphur has been heated to atemperature above that at which the reaction with carbon takes place, itprovides suicient heat to raise the carbon to reaction temperature sothat whenever the sulfur comes in contact with the carbon, reaction canoccur. As a result of this, the sulfur content of the gases `issuingfrom the outlet 61 is relatively small as compared to the sulfur contentof the reaction products issuing from the usual reactors knownheretofore.

When it is desired to clean the retort, the feed of carbon is cut offand the carbon mass in the retort is permitted to diminish by reactionuntil Lonly a relatively small quantity of carbon is present. The feedof sulfur is also cut off until finally the reactor is free of sulfur.The reactor is then opened, the absence of any sulfur or carbonbisulphide in the retort materially simplifying the operation. When thecarbon feed and sulfur feed are again resumed, the retort can be quicklybrought on stream inasmuch as the sulfur carries the heat into thecarbon mass and it is not necessary to wait for any substantial periodfor the freshly introduced carbon to attain reaction temperature. Inaddition, there is much less thermal shock ,when the retort is open tothe atmosphere inasmuch as the air passes up through the mass of carbonand Vthe in- `terior of reaction vessel 31 and not over the ironsulphide `coated surfaces of the outer vessel v12 and the intermediatevessel 18.

In the .Previously described form vof furnace, liquid sul- ,fur is fedto the reactor, being vaporized and superheated within the retort. Inthat form of retort structure shown in Figures 7 and 8, the sulfur isvaporized externally of the retort and is fed to the retort as a vapor.Thus, as is shown in Figures 7 and 8, retort 71 is mounted vertically inthe furnace, the latter being indicated by brick work outlined at 72.The retort 71 comprises a vertical vessel, generally of annular section,extending upwardly above the furnace and having an ash boot 73 extendingexternally of the furnace so that ash `and unused carbon can be removedperiodically, as desired. At its upper end, the vessel includes aVflange 79 on which rests a spool 74 having a carbon bisultide outlet 76and a feed inlet 77.

ln accordance with this invention, a tubular shell 78 is mounted withinthe furnace, preferably depending from flange 79 in a spaced parallelrelation to the inner vertical surface of vessel 71 to providerelatively narrow space between the vessel and the shell through whichsulfur vapor passes. Fnrther, in accordance with this invention, asulfur vaporizer, Ygenerally indicated at 81, is mounted within thefurnace 72 to receive heat therefrom land including a vaporizing pot 82a liquid sulfur feed inlet 83, and a sulfur feed pipe 84 through whichliquid sulfur is supplied to the vaporizer 82. A sulfur vapor otftalepipe 86 extends from an upper portion of the vapori'zer to the upperportion of shell 81, a tangential inlet 87 being provided in the retortshell whereby sulfur vapor from pipe 83 is discharged tangentiallybetween tubular shell Aand outer retort vessel 71.

It is preferred that a plurality of fins 89 extend radially downwardlyabout the tubular lshell 78 to direct the sulfur vapor downwardly4between the two and provide a relatively elongated and tortuons pathbetween the vessel and the shell whereby the sulfur vapor passesdownward- 1y, to emerge and pass upwardly through the charcoal masswhichis within the tubular vessel 78. If desired, tubular shell 78 c anbe supported from the bottom of the outer vessel 71 in a spacedrelation. In any case, it is desirable to seal thevesseland shelladjacent their upper ,ends S0 that the Sulfur dahrrot ,Short circuit andpass direct- 1y through the upper pdrtidh Of the traveling bOdy 0fcarbon. i

From the foregoing, .it will be apparent that I have provided arelatively? novel, simple and improved forth 0f Carbon bishltdr furnaceI claim:

l. A carbon bisullide retort comprising a furnace, an Outer tubularvessel positioned vertically in said furnace for heating by the furnace,an inlet adjacent the .bottom of said outer vessel for feeding vsulfurto be Vheated in said outer vessel, an intermediate tubular vesselposiytioned verticallyin and spaced from said outer vessel and open atits upper end to admit sulfur .vapor passing upwardly in the spacebetween said vessels to the interior of said intermediate vessel, an ashoutlet adjacent L.the bottom of the intermediate vessel, an innertubular shell supported adjacent the upper ,end of the outer tubularvessel and depending to'adjacent the bottom lof the intermediate vesselinv a spaced wall relationship to said intermediate vessel, and a sealbetween said inner tubular shell and said outertubular Vessel.

2. A carbon bisulde retort rcomprising a furnace, an outer tubularvessel having a bottom and positioned vertically in said furnace forheating by the furnace, an inlet adiaht the bOttOrh of Said Outer vesselfor feeding sulfur to b e heated and vaporized on the bottom in saidouter vessel, an intermediate tubular vessel supported on the bottom ,ofVthe outer vesselland positionedvertically lin and spaced from saidouter vessel having a bottom and open at its upper `rhdto admit SulfurvapQr passing upwardly from said Outer-vessel bottom ih the .Space be-.tween Said vessels. t0 the interior of ,Saidgintermdiate vsse1 an,ashoutlet adjacent the fhsttdm of lthe .inter mediate vessel, kandirtrlertubular Shell ,Supphrted adjacent thwart-ir 11d df the-furnace and theouter tubular-vessel @ridden f-t0 hdiaaeht ,tht-batte@ stt-theintermediate,

vessel in a spaced wall relationship to said intermediate vessel, and aseal between said inner tubular Shell and said outer tubular vessel.

3. A carbon bisulde retort comprising a furnace, an outer tubular vesselpositioned vertically in said furnace for heating by the furnace, aninlet adjacent the bottom of said outer vessel for feeding sulfur to beheated in said outer vessel, an intermediate tubular vessel positionedvertically in and spaced from said outer vessel and open at its upperend to admit sulfur vapor passing upwardly in the space between saidvessels to the interior of said intermediate vessel, an ash outletadjacent the bottom of the intermediate vessel, an inner tubular shellsupported adjacent the upper end of the outer tubular vessel anddepending to adjacent the bottom of the intermediate vessel in a spacedwall relationship to said intermediate vessel, a seal between said innertubular shell and said outer tubular vessel, a tubular receptaclepositioned above said inner tubular shell and in communication therewithfor feeding carbon to said inner shell and to said intermediate vessel,and an outlet for carbon bisulde from said tubular receptacle.

4. A carbon bisulfde retort comprising a furnace, an outer tubularvessel positioned vertically in said furnace for heating by the furnace,an inlet adjacent the bottom of said outer vessel for feeding sulfur tobe heated in said outer vessel, an intermediate tubular vesselpositioned vertically in and spaced from said outer vessel and open atits upper end to admit sulfur vapor passing upwardly in the spacebetween said vessel to the interior of said intermediate vessel, an ashoutlet adjacent the bottom of the intermediate vessel, an inner tubularshell supported adjacent the upper end of the outer tubular vessel anddepending to adjacent the bottom of the intermediate vessel in a spacedwall relationship to said intermediate vessel, a seal between said innertubular shell and said outer tubular vessel, an outer receptaclepositioned above said inner tubular shell for feeding carbon to saidinner tubular shell, and an outlet for withdrawing gaseous products,including carbon bisulde from the outer receptacle.

5. A carbon bisulfde retort comprising a furnace, an outer tubularvessel having a bottom and positioned vertically in said furnace forheating by the furnace, an inlet adjacent the bottom of said outervessel for feeding sulfur to be heated and vaporized on the bottom insaid outer vessel, an intermediate tubular vessel supported on thebottom of the outer vessel and positioned vertically in and spaced fromsaid outer vessel having a bottom and open at its upper end to admitsulfur vapor passing upwardly from said outer vessel bottom in the spacebetween said vessels to the interior of said intermediate vessel, an ashoutlet adjacent the bottom of the intermediate vessel, an inner tubularshell supported adjacent the upper end of the furnace and the outertubular vessel and depending to adjacent the bottom of the intermediatevessel in a spaced wall relationship to said intermediate vessel, a sealbetween said inner tubular shell and said outer tubular vessel, an outerreceptacle positioned above said inner tubular shell for feeding carbonto said inner tubular shell, and an outlet for withdrawing gaseousproducts, including carbon bisulde, from the outer receptacle.

6. A carbon bisulde retort comprising a furnace, an outer tubular vesselhaving a bottom and positioned vertically in said furnace for heating bythe furnace, an inlet adjacent the bottom of said outer vessel forfeeding sulfur to be heated and vaporized on the bottom in said outervessel, an intermediate tubular vessel supported on the bottom of theouter vessel and positioned vertically in and spaced from said outervessel having a bottom and open at its upper end to admit sulfur vaporpassing upwardly from said outer vessel bottom in the space between saidvessels to the interior of said intermediate vessel, an ash outletadjacent the bottom of the intermediate 6 v vessel, an inner tubularshell supported adjacent th upper end of the furnace and the outertubular vessel and depending to adjacent the bottom of the intermediatevessel in a spaced wall relationship to said intermediate vessel, a sealbetween said inner tubular shell and said outer tubular vessel, an outerreceptacle positioned above said inner tubular shell for feeding carbonto said inner tubular shell, an outlet for withdrawing gaseous productsincluding carbon bisulde from said outer receptacle, and means forfeeding carbon substantially continuously to said outer receptacle.

7. A carbon bisuliide retort comprising a furnace, an outer tubularvessel having an upper end, a lower end, a vertical side wall and abottom, said vessel being positioned vertically in said furnace forheating by said furnace; an inner tubular shell having open upper andlower ends and supported intermediate the ends of the outer vessel andin a uniformly spaced relation to the vertical side wall of the outervessel and with its lower open end spaced from the bottom of the outervessel and with its open upper end spaced from and being below the upperend of the outer tubular vessel; the outer vessel and the inner shelleach being substantially cylindrical with the inner shell substantiallyconcentric with the outer vessel; a seal between the upper end of theinner vessel and side wall of the outer vessel intermediate the ends ofthe outer vessel; a carbon inlet in the upper end of the outer vesselfor feeding carbon for passage downwardly through the upper portion ofthe outer vessel and then into said shell; and an inlet for introducingsulfur for passage as vapor from adjacent said seal downwardly over theouter surface of the inner shell, past the lower end of the inner shelland thence upwardly into contact with carbon in the inner shell.

8. A carbon bisulflde retort comprising a furnace, an outer tubularVessel having a vertical side wall and a bottom, said vessel beingpositioned vertically in said furnace for heating by the furnace, aninner tubular shell having an open upper and lower end and supportedintermediate the ends of the outer tubular vessel and in a spacedrelation to the vertical side wall of the outer vessel and having itsopen lower end spaced from the bottom of the outer vessel and with itsopen upper end spaced from and being below the upper end of the outertubular vessel; the outer vessel and the inner shell each beingsubstantially cylindrical with the inner shell substantially concentricwith the outer vessel; a seal between the upper end of the inner vesseland the outer vessel, means for feeding carbon into an upper portion ofthe outer shell and thence into the inner shell, an inlet forintroducing sulfur into the outer vessel for passage as vapor fromadjacent said seal downwardly over the outer surface of the inner shelland thence past the lower end of the inner shell into contact withcarbon in the shell, and an outlet for removing to the exterior of theouter vessel unreacted carbon and ash issuing from the inner shell.

9. A carbon bisulde retort comprising a furnace, an outer tubular vesselhaving a vertical side wall and a bottom, said vessel being positionedvertically in said furnace for heating by the furnace, an inner tubularshell having an open upper and lower end and supported in a spacedrelation to the vertical side wall of the outer vessel and having itsopen lower end spaced from the bottom of the outer vessel, a sealjoining the upper end of the inner vessel to the outer vessel, means forfeeding carbon into an upper portion of the inner shell, and an inletfor introducing sulfur tangentially between the outer vessel and theshell adjacent the upper end of the shell for passage as vapor betweenthe inner surface of the outer vessel and the outer surface of the shelland thence about the open lower end of the shell and into contact withcarbon in the shell.

l0. A carbon bisulde retort comprising a furnace, an outer tubularvessel having a vertical side wall and a bottom, said vessel beingpositioned vertically in said furnace for heating by thefurnae an innertubular Shell having an @een upper and I Qwer @nd and Supperted in aspaced relation to the vertical side wall of the outer vessel and`having its open lower end spaced frorn the bottom of thcouter vessel, aseal joining the upper end of the inner vessel to the outer vessel,means for feeding carbon into an upper portion 0f the inner shell, aninlet for introducing sulfur tangentially between the youter vessel andthe shell adjacent the upper lend of the shell for passage as vaporbetween theinner surface of the outer vessel and the outer surface ofthe shell and thence about the open lower end of the shell and intocontact with carbon in Vthe shell, and means between the shell and thevessel providing an elongated path for sulfur vapor moving downwardlyover said shell.

l1. A carbon'bisulde retort comprising a furnace, an outer Ltubularvessel lhaving a vertical side wall and a bottorn, saidvessel beingpositioned vertically in said fur nace for heating by the furnace, aninner tubular shell supported in a spaced relation to the vertical sidewall of the outer vessel and having its lower end spaced from thebottorn of the outer Vessel, a seal'joining the upper end of the innervessel to the outer vessel, means for feeding carbon into an upperportion of the shell, means for introducing sulfur vapor tangentiallyinto the space between the outer vessel and the shell below said sealfor passage downwardly as vapor over the outer surface of the innervessel and past the lower end of the shell into contact with carbon inthe shell, and a plurality of fins provided between the shell and thevessel and providing a circular path for sulfur vapor to traverse as itmoves downwardly between the shell and the vessel.

References Cited in the le of this patent UNITED STATES PATENTS1,614,791 Hamilton Jan. 18, 1927 1,738,620 Umpleby Dec. 10, 19292,200,475 Legeler May 14, 1940 2,577,729 Bauer Dec. 11, 1951 2,577,786 MacDOugall Dec. 11, 1951 2,656,254 Heller Oct. 20, 1953

1. A CARBON BISULFIDE RETORT COMPRISING A FURNACE, AN OUTER TUBULARVESSEL POSITIONED VERTICALLY IN SAID FURNACE FOR HEATING BY THE FURNACE,AN INLET ADJACENT THE BOTTOM OF SAID OUTER VESSEL FOR FEEDING SULFUR TOBE HEATED IN SAID OUTER VESSEL, AN INTERMEDIATE TUBULAR VESSELPOSITIONED VERTICALLY IN AND SPACED FROM SAID OUTER VESSEL AND OPEN ATITS UPPER END TO ADMIT SULFUR VAPOR PASSING UPWARDLY IN THE SPACEBETWEEN SAID VESSELS TO THE INTERIOR OF SAID INTERMEDIATE VESSEL, AN ASHOUTLET ADJACENT THE BOTTOM OF THE INTERMEDIATE VESSEL, AN INNER TUBULARSHELL SUPPORTED ADJACENT THE UPPER END OF THE OUTER TUBULAR VESSEL ANDDEPENDING TO ADJACENT THE BOTTOM OF THE INTERMEDIATE VESSEL IN A SPACEDWALL RELATIONSHIP TO SAID INTERMEDIATE VESSEL, AND A SEAL BETWEEN SAIDINNER TUBULAR SHELL AND SAID OUTER TUBULAR VESSEL.